These are but a sampling of the extraordinary "sensory adventures" guests can savour as part of Crystal Cruises’ Northern European voyage collection that begins this May. Other shore-side excursions include:

Historical journeys related to Vikings in Stockholm, Dublin and Roskilde (near Copenhagen); genealogical emigration and the Cold War in Hamburg; and life behind Berlin’s Iron Curtain

Architectural tours spanning the Art Nouveau in Ålesund, Norway to the Modern in Berlin, plus eco-conscious trips like bird-watching in Runde Island (near Ålesund) and Shetland; kayaking the Finnish Archipelago (Helsinki); and exploring the wind-powered town of Paldiski (near Tallinn) by 4x4.

Adrenalin-fuelled adventures such as racing rally cars in Estonia; cosmonaut training, including zero-gravity weightlessness, near Moscow; and, in Crystal’s most over-the-top excursion of 2011, flying a MiG fighter jet over Russia - for $39,300.

Expanding on its “You Care, We Care” voluntourism initiative, Crystal is also offering a couple of excursions where guests can “give back” by packing and donating food at the Estonian Food Bank or volunteer at the Rostock Zoological Garden. These excursions are complimentary with Crystal Cruises, covering all logistical arrangements and costs.

Prices for Crystal’s Northern European voyages start from £4,207 per person (based on a May 22 departure), including free return economy flights, 11 nights in a deluxe stateroom with picture window, with all meals, soft drinks and port taxes.

In addition, as part of Crystal's "All Inclusive - As You Wish" promotion, guests on this voyage will also receive onboard spending money of $1,000 per person, which can be spent on shore excursions, spa treatments, alcoholic beverages, purchases in the onboard boutiques, gratuities or Vintage Room experiences.